.main {
    padding: 20px 0;
    min-height: calc(100% - 140px);
}
.main_container {
    position: relative;
    width: 960px;
    margin: 0 auto 0 auto;
}
.books_left {
    width: 730px;
    float: left;
    background: #fff;
    box-shadow: 0 8px 16px 0 rgba(7,17,27,.05);
    border-radius: 12px;
    box-sizing: border-box;
    padding: 40px 40px 24px 40px;
    position: relative;
    margin-bottom: 80px;
}
.books_title {
    font-weight: 700;
    font-size: 24px;
    border-bottom: 1px solid #bfb2b2;
}
.books_items {
    margin-top: 1em;
}
.books_item {
    line-height: 30px;
    font-size: 16px;
    /*font-weight: 600;*/
    color: #3273dc;
    cursor: pointer;
}

.books_right {
    width: 207px;
    float: right;
    background: #fff;
    box-shadow: 0 8px 16px 0 rgba(7,17,27,.05);
    border-radius: 10px;
    box-sizing: border-box;
    position: fixed;
    right: 22%;
}
.books_types {
    margin: 1em auto;
    list-style: none;
    padding-left: 1.5em;
    padding-right: 1.5em;
}
.types_item {
    cursor: pointer;
    line-height: 30px;
    font-size: 16px;
    color: #3273dc;
    border-bottom: 1px solid;
}